A service call on the South Shore: a condenser at a complete standstill
A homeowner in Châteauguay , on the South Shore of Montreal , contacted us after noticing that his KeepRite central system was no longer starting. The indoor blower was operating normally, but no signal was being transmitted to the outdoor condenser , and the fan remained stationary.
On-site, our AirGreen team immediately identified a KeepRite central heat pump unit, installed on a flat, gravel-covered roof typical of multi-unit residential buildings. The client, concerned about the approaching warm weather, wanted to ensure their system was repaired before the peak summer season.
KeepRite Condenser In-Depth Diagnostics
The diagnosis began with a complete visual inspection. Upon removing the front hood, several things caught our attention:
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Significant accumulation of dust and debris on the control board and main contactor.
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Frozen fan , indicating possible start capacitor failure.
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There were no burn marks on the cables or the connection terminal, which ruled out a major electrical fault.
Step 1: Check the power supply
We measured a stable voltage of 240 volts , confirming that the power supply was correct. However, no current was flowing to the fan motor , indicating a faulty start capacitor .
Step 2: Test the Capacitor
Using a digital multimeter, we measured the capacitance of the combined capacitor (fan + compressor).
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Nominal value: 45/5 µF
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Measured value: 12/1 µF
This significant difference confirmed advanced wear of the component, typical after several years of exposure to heat and vibrations.
Complete repair and return to service
We have carried out a refurbishment of the starting circuit :
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Replacement of the capacitor with a new model, of the same capacity and nominal voltage (440 V).
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Complete cleaning of the electrical compartment and the condenser with compressed air.
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Check the contactor (no excessive tapping or electric arcing).
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Measurement of intensities after start-up:
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Compressor: 8.2 A (within standards).
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Fan: 1.3 A (stabilized after 30 seconds).
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Once the system was restarted, the air temperature at the duct outlet dropped from 24°C to 12°C — proof of optimal performance.
AirGreen Results and Maintenance Tips
The client immediately noticed the return of comfort and fresh air flow in all rooms. This type of intervention is a classic at the start of summer , often linked to a lack of spring maintenance.
Our technicians took advantage of the visit to recommend some good preventive practices :
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Check the capacitor and contactor annually , especially on systems exposed to the sun.
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Clean the condenser fins to prevent overheating.
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Monitor fan vibrations , which are sources of premature deterioration.
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Perform a complete maintenance before the hot season , including gas pressures, leak testing and electrical calibration.
A tired capacitor can cause random restarts, excessive power consumption and even compressor failure , a much more expensive repair.
AirGreen expertise at the service of central systems
This repair in Châteauguay perfectly illustrates our expertise in repairing KeepRite central heat pumps . Our technicians master every step of the process—from diagnosis to recommissioning—with a rigorous approach that respects HVAC standards.
At AirGreen , we operate throughout Greater Montreal, Laval, Longueuil, the North Shore and the South Shore , for the brands KeepRite, Trane, Goodman, Lennox, Comfortmaker, Midea, Fujitsu and many others . Each intervention aims to restore comfort and maximize the system's energy performance , while ensuring increased sustainability.
AirGreen — your trusted HVAC specialist for central heat pump repair in Greater Montreal.